In a method of fabricating a semiconductor device, cleaning is conventionally carried out to remove any attachment adhering to the surface. The technique of such cleaning methods are disclosed in, for example, Japanese Patent Laying-Open No. 4-354334 (Patent Literature 1) and Japanese Patent Laying-Open No. 6-314679 (Patent Literature 2).
The method of cleaning a semiconductor disclosed in Patent Literature 1 has foreign object components adhering to the surface removed by spraying pure water including 1-5 ppm ozone to the semiconductor to cause ozone oxidation.
The method of cleaning a semiconductor substrate disclosed in Patent Literature 2 includes the steps of rinsing a silicon (Si) substrate with ultra pure water including ozone to form an Si oxide film, capturing particles and metal impurities into and/or on the surface of the Si oxide film, cleaning the Si film with dilute hydrofluoric acid aqueous solution to etch away the Si oxide film and remove the particles and metal impurities at the same time.
The technique of using ozone in the process of fabricating a semiconductor device is disclosed in Japanese Patent Laying-Open No. 2002-33300 (Patent Literature 3), for example. Patent Literature 3 teaches the approach of supplying ozone-containing pure water into an ozone water contactor, based on the condition that the ozone-containing pure water attains a temperature greater than or equal to approximately 22° C. and a dissolved ozone concentration greater than or equal to approximately 30 ppm, bringing the substrate including a remaining photoresist film in contact with the ozone-containing pure water to remove the photoresist film.